Breaks act as automatic safeguards to prevent the organism from working continuously

Break. --In spite of the insignificance of the work decrement and of the variety of reinforcements which have been utilized to maintain the same level of work output, there come times when performance ceases altogether. This may be referred to as "break." Prolonged activity may be interrupted by demands for food or sleep, by some competing task, or by the gradually increasing insistence of inhibitory effects occasioned by thirst, eye strain, and muscular pains. Real fatigue may be a contributing factor here, but the apparent work decrement may bear no regular relation to the degree of absolute fatigue in the tissues which performed the discontinued task. Breaks act as automatic safeguards to prevent the organism from working continuously; they can never be fully understood if we regard them as the direct product of fatigue, but only in connection with intercurrent competing tendencies.

A prolonged period of monotonous work like correcting examination papers finds before its close some insistent demand for interruption. If I successfully suppress one demand, more insistent ones arise, until finally effective voluntary reinforcement of the main task suddenly ends. The voluntary reinforcements may have developed such sensations of strain that the surrender to a competing impulse brings great relief. I know that the interruption is not permanent. I consent to it to get the competing matter off my mind, expecting to return presently to the main task, freed from the incubus of that particular competitor. In very much the same way, after lying awake for a time on one side we turn over, not because we could not lie on that side longer, not because we expect any great improvement in comfort from the change, certainly not because we expect to lie on the other side forever. . . . Possibly social unrest follows a similar course.

The body politic seeks a change in government, or in social and economic conditions, not because the present is really unendurable, not because it expects a permanent betterment. . . . I suppose all the phenomena of restlessness and the corresponding attractiveness of change finally reduce to competition. It operates in work and play, in social and economic activities, in politics and in religion. Without its interference in our lives, unwelcome as it sometimes is, we must have continued indefinitely in the direction of our first activity . . . to the final collapse of complete exhaustion.